Automatic offsetting device for saw-iviill carriages



(No Model.)

3 Sheets-Sheet 1. A. E. SMITH. I AUTOMATIGOFFSETTING DEVIGB FOR SAW MILL GARRIAGES.

Patented Dec. 23, 1890.

WITNESSES.-

7 A rromvns.

A s Shets-Sheet 2.

(No Model.)

. v A. E. SMITH. AUTOMATIC OPPSETTING DEVICE FOR SAW MILL OARRIAGES.

Patented Dec. 23,1890.

IIVVENTOI? WITNESSES:

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(No Model.) 3 sheets-sheet 3.

v A. E. SMITH. AUTOMATIC OFFSETTING DEVICE FOR SAW MILL GARBIAGES.

No. 443,336. Patented Dec. 23; 1890.

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MvM'W eflwormys UNITED STATES PATENT OFFICE.

ALBERT E. SMIT or WAUSAU, WISCONSIN.

AUTOMATIC OFF SETTING DEVICE FOR SAW-MILL CARRIAGES.

SPECIFICATION forming part of Letters Patent No. 4 43,3916, dated December 23, 1890.

Application filed June 13, 1890. Serial No. 355,339. (No model.)

To to whom it may concern.-

Be it known that I, ALBERT E. SMITH, a citizen of the United States, residing at Wausau, in the county of Marathon and State of .Wisconsin, have invented certain new and useful Improvements in Automatic Offsetting Devices for Saw-Mill Carriages; and I do hereby declare the following to be a full,.clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and usethe same.

My invention relates to offsetting devices in saw-mill carriages, and is more particularly appropriate for band-sawmill carriages.

The fundamental principle of my invention is that a small strain upon the payingout end of a rope or chain wound around a revolving drum or capstan is sufficient to keep the rope or chain from slipping on the. drum or capstan.

'My invention consists of a rope or chain wound upon one, two, or more drums rigidly attached to as many axles of the carriage or upon a drum on a shaft whose motion is always in the same direction as that of the axles,

the rope or chain having weights attached to its ends, whereby friction is maintained between the drums and the rope, and suitable arms on a bar acted upon by clamps on the rope. This baris given a longitudinal motion by the said drums, ropes, and clamps, which motion is converted into a lateral motion of the carriage by suitable devices.

In my invention the excessive friction of the offsetting device common in nearly all offsetting carriages is practically done away with, there being no power consumed except during the time the carriage is in lateral motion. I have shown in the drawings three of many methods by which this power can be so changed and directed, one being a togglejoint, a second a casting with part of a screwthread engaging therein, and a third a rack and quadrant, all to be hereinafter more fully described. Motion is imparted to the drums by the friction of the wheels on whose axles the drums are rigidly secured. On one side of the carriage the trucks are grooved and run over a track adapted to lit in said groove. The axles are arranged to have a longitudinal play of three-quarters of an inch, so that the distance required for offsetting.

the carriage may be drawn away from the saw-line and moved back to it again through the space of three-quarters of an inch. Thus it will be seen that the axles are held rigidly against longitudinal motion, while the carriage can be slid sidewise upon the axles for The journals of the axles fit snugly, so as to prevent wabbling.

' In the drawings, where similar parts are i11- dicated by similar letters and figures, Figure 1 represents a vertical section through the drums D D and across the axles A A of the carriage. Fig. 2 represents the plan view of the carriage with my improvements thereon. Fig. 3 represents another form of applying my invention to offsetting the carriage. Fig. 4. represents a third form of applying my invention to offsetting the carriage, the cross-beam J being thrown up to better show the portion of nut 6 for the screw-thread 7. Fig. 5 represents the manner in which the weights V W are attached to the rope C. Fig. 6 represents the weight IV or W with its lugs sliding along the guides L L. Fig. 7 represents another form of my device. Figs. 8, 9, and 10 represent the method by which two separate ropes leading from the weights W and W, respectively, may be employed in lieu of one continuous rope and the method by which the slack may be taken up if the rope stretches. Fig. 11 represents the end of the locking-bar and bent lever K.

To describe my invention more fully, A A represent the axles of the carriage, having a side play of three-quarters of an inch in their boxes or journals.

I I represent the side timbers of the carriage.

J J represent the cross-timbers of the carriage.

X X represent the grooved wheels running on a i);ongued track. (Not shown in the draw lugs.

Y Y represent the wheels next the saw-line; Z Z, the hubs.

B represents the offset-bar, preferably of about one-and-a-half-inch pipe.

0 is the rope wound around the drums D D, rigidly attached to the axles A A.

cc are clamps attached to the rope. These clamps take against the lugs or arms E It, imparting the motion of the ropes to the offsetbar 13.

F F are two pulleys, converting the horizontal motion of the rope to the vertical motion pursued by the weights W and W. This direct motion of the offsetting-bar is converted into a lateral motion of the carriage by the toggle-joints Q and Q, as shown in Fig. 2,01- by the rack 3, secured to the edge of a crossbeam J of the carriage, engaging the quadrant 2, pivoted to a loose collar held between two set-collars on the axle, said quadrant being actuated by the rod B and clamps c c, as in Fig. 2, or by the portion of nut 6 and screw 7, as shown in Fig. 4, where 5 is an arm held between two set-collars 17 on the axle, said axle revolving within the lower end of the arm 5, and said arm being actuated by the rod B and clamps c c, as in Fig. 2, or by any other equivalent mechanical means.

Inasmuch as it is desired to have the carriage moved quickly sidewise, either toward or away from the saw-line, I have arranged the drums, ropes, &c., so that a motion of the rope of three inches and the corresponding motion of the bar of three inches will move the carriage laterally three-quarters of an inch, while the carriage is traveling about four inches. In Fig. 2 this is accomplished either by regulating the length of the two arms of my toggle-joints T T or T T or by increasing the distance moved over by the rope and offset-bar. In Fig. 3 this is arranged by making the arm of the quadrant attached to the bar four times as long as that engaging in the rack secured to the frame of the carriage, while still limiting the motion of the rope to three inches. In the screw device, as shown in Fig. 4, a similar mechanical arrangement is made; but I do not care to limit myself to any exact throw or offset of the carriage, as it will be readily seen that by the substitution of longer or shorter axles and altering the distance the weights IV and W travel I may offset my carriage to any distance dc sired.

The motion of the rope is regulated by the distance through which the weights W and \V move, and this distance is adjusted by lengthening or shortening the rope between \V and and raising or lowering the weightsupports Z by means of the nuts P. This can be done in many ways; but it maybe readily and conveniently done by having two distinct ropes, each spliced into its own weight and leading to the device shown in Figs. 8, 0, and 10, which is placed between the drums. Ilere one end of the rope is knotted after reaving through a hole 13 in the plate 12. The other rope is rove through the other two holes in the plate 12 and is jammed in place by the plate 18 and bolts 11. Now if it is desired to take up or case off on the rope, unscrew the nut on. the bolt 11, adjust the rope, and clamp it again by screwing down hard on the nut 1-1. The bolts 1.1 have nuts 14-, which may be set at any required position. The bolt-holes 15 in the lower or clamping plate are elongated to allow the plate to fall somewhat, so that. the rope may be easily inserted and the plate brought back ready for clamping.

In the drawings, Figs. 1 and 2, I represent my carriage as offset and ready for gigging back to take another cut. The weight W being up, when the carriage moves in the direction indicated by the arrow the drums will revolve. The tension of the weight \V on the rope going around the drum will be sufficient to create considerable friction, (with a weight of ten pounds'and three turns of the rope on one drum I get a pull of seven thousand two hundred and ninety pounds) and the clamp 0 will pull against the arm E, bending the toggle-joint T T, causing the carriage to be drawn to the cross-pieces R and R, rigidly secured to the axles of the carriage. This will throw the carriage againstthe hubs of the wheel Y Y and place it in position for another cut. As soon as the weight \V has fallen through three inches, it will rest on the bolt-heads at the bottom of the guides L. The rope being no longer held on the drum, the drum will revolve beneath it with very little friction, and the carriage will continue on its course until the end of the cut is reached.

I show two drums in the drawings to avoid any accident from having one pair of wheels slip; but my device is equally applicable where one or any number of drums are used, or where a drum on any shaft having a mo tion in the same direction as the axlesis used. Thus I may have one or more drums 011 as many independent shafts, having on each shaft a pinion engaging in a rack beneath the carriage, whereby the motion of the carriage causes the drums to revolve; but inasmuch as there could be no slipping of the pinion in the rack one drum, as shown in Fig. 7, would be sufficient. In the said figure, 20 is the rack secured to the carriageplatform between the tracks, which platform is not shown. 21 is a pinion engaging-in said rack and keyed on the shaft revolving in journals attached to the side timbers of the carriage. The drum I), having two or more turns of the rope is keyed on the same shaft. The rod 13 is moved by the arms E E and clamps c c, as in Figs. 1 and 2; but the offset is given by the arm 5 and portion of screw-thread ti, (an anti-friction roller may be substituted and the slot may be made rectilinear, thus producing the effect of a fixed roller pressiu g away a movable inclined plane or wedge,) the screw-thread or roller being held rigidly against lateral motion, while the carriage has a small play sidewise for the purposes of offsetting. It will be seen that as the weight \V descends the weight \V will rise, and that if the motion of the carriage be reversed the clamp a will take til against the arm E the carriage will be pushed away from the cross-pieces R and R and it will ofiset automatically. This is as it should be when a out has been completed; but should it be desired at any time before the cut is finished to back the saw out it will be necessary to support the weight NV and so prevent the offset from taking place and the saw from being injured. For this purpose, when it is necessary for the saw to be backed out before the out has been completed, I have the hand-lever H pivoted to the side of the carriage. Bypulling upon this lever in the direction shown by the arrow, the arm (better shown in Fig. 11) of the bent lever pivoted at O to the end of the guide L of the weight W, is thrown under the lug M of the weight WV, taking its weight. This takes the tension off the rope, and so prevents the rope from pulling on the oifset-bar, tending to olfset the carriage.

I do not wish to limit myself to the devices described and shown, as many modifications would readily suggest themselves to a skilled mechanic which could be used without departing from the spirit of my invention.

I do not claim the toggle-joint Q and Q, the quadrant and rack 2 and 3, Fig. 3, or the screw and casting 6 and 7, Fig. 4, these being all well-known mechanical means of converting a direct motion into one at right angles to itself; but

\Vhat I do claim, and desire to secure by Letters Patent, is

1. In a saw-mill carriage, the combination of a laterally-movable carriage-frame, a drum or drums rigidly secured to one ormore shafts set across the said carriage-frame and revolved simultaneously with the wheels of the carriage by any suitable mechanism, a rope or chain wound around the drum or drums, weights suspended at the ends of said ropes or chains to increase the friction around the drum or drums, and any suitable mechanical device for converting the longitudinal motion of the rope or chain into the lateral motion of the carriage.

2. In a saw-mill carriage, the combination of a laterally-movable carriage-frame, a drum or drums rigidly secured to one or more shafts set across the said carriage -frame and revolved simultaneously with the wheels of the carriage by any suitable mechanism, a rope or chain wound thereon and kept in a state of tension by weights W and \V, and the clamps c c on the said rope or chain working against shoulders on an offset-bar, whereby the motion of the ropes is transmitted to the said bar to offset the carriage, as herein set forth.

3. In a saw-mill carriage, the combination, with a laterally-movable carriage-frame, of a drum or drums rigidly secured to one or more shafts set across the said carriage-frame and revolved simultaneously with the wheels by any suitable mechanism, a rope or chain wound on the said drum or drums, weights attached to the ends of said rope or chain, and

guides for the said weights, provided at their lower ends with lugs to. stop the downward motion of said weights, as and for the purposes described.

4, In a saw-mill carriage, the combination, with a laterally-movable carriage-frame, of a drum or drums secured to one or more shafts set across the carriage and revolving simultaneously with the wheels of the carriage, a rope or chain wound on the said drum or drums, weights attached to the ends of said rope or chain, and guides for the said weights, provided at their lower ends With lugs to stop the downward motion of said Weights, with adjusting devices for guides, substantially as described.

5. In a saw-mill carriage, the combination of a laterally-movable carriage-frame, a drum or drums rigidly secured to one or more axles, a rope or chain wound around the drum or drums, weights suspended at ends of said ropes or chains to increase the friction around the drum or drums, and any suitable mechan ical device for converting the longitudinal motion of the rope or chain into the lateral motion of the carriage.

6. In a saw-mill carriage, the combination of a laterally-movable carriage-frame, a drum or drums secured to the axles of the carriage with a rope or chain wound thereon and kept in a state of tension by weights W and W, and the clamps c c on the'said rope or chain working against shoulders on an offset-bar, whereby the motion of the ropes is transmitted to the said bar to offset the carriage, as herein set forth.

7. In a saw-mill carriage, the combination, with a laterally-movable carriage-frame, of a drum or drums on the axles, a rope or chain wound on the said drum or drums, weights attached to the ends of said rope or chain, and guides for the said weights, provided at their lower ends with lugs to stop the downward motion of said weights, as and for the purposes described.

8. In a saw-mill carriage, the combination, with a laterally-movable carriage-frame, of a drum or drums on the axles, a rope or chain wound 011 the said drum or drums, weights attached to the ends of said rope or chain, and guides for the said weights, provided at their lower ends with lugs to stop the downward motion of said weights, with adjusting devices for said guides, substantially as described.

9. In a saw-mill carriage, the combination of the'lat-erally-movable carriage-frame, the drums D and D on the axles A A, the rope or chain 0 and pulleys F and F, weights W and W, guides L and L, and clamps c and c, engaging arms E and E on the offset-bar B, whereby the motion of the rope is transmitted to the offset-bar B and to the arm 5,fitt-ing in a collar on the axle A and having a screwthread 6 engaging on the casting 7 on the cross-piece J of the frame of the carriage,

securing the ends of the ropes attached to the weights \V and the slotted plate 12,11aving three holes for the rope, the bolts 11 11 and 11, nuts ll ll and ll, and plate 8, capable of being screwed toward the plate 12, substantially as described.

In testimony whereof I afl'ix my signature in 20 presence of two witnesses.

ALBERT E. SMITH. Witnesses:

1 J. TYRRELL, \VILLIAM WILSON. 

